.

Diseases, caused by absence of vitamins from food, 42;
carried by mosquitoes and flies, 71;
caused by focal infection, 82;
preventability of, 135-136;
relation between consumption of alcohol and increase in degenerative,
235-236;
effect of alcohol on bodily resistance to, 239-240;
caused by smoking, 263-264;
signs of increase of the degenerative, 281-285.

Disinfection of foods, 43.

Drafts, unreasonable prejudice against, 8;
exaggeration of idea that colds are derived from, 8-9;
popular delusions concerning, 123-124;
exposure to, a means of skin training, 274;
avoidance of, after catching cold, 277.

Drugs, avoidance of, for constipation, 53;
habit-forming, as poisons, 65;
alcohol to be classed among, 242.

Dryness of air, 11, 19;
question of ill effects from extreme, 12.

Duodenum, ulcer of, caused by focal infection, 82.

Dust, air vitiation from, 13;
methods of removing, 13;
bacteria carried by, 13-14.

Dusty trades, morbidity and mortality rates in, 13.

Dyspepsia among smokers, 264.

Eating, before retiring, 103;
in case of colds, 279-280.

Eating habits. _See_ Food.

Education on inheritability of traits, need of, 323.

Eggs, food value of, 29, 38, 183;
for underweight, 220.

Emetin, use of, in treating pyorrhea, 85-86.

Emotions, exercise of the, 97.

Endurance, experiments to determine effect of different diets on,
197-199;
experiments with mastication, and instinctive eating, 200-209.

Enema, use of, for constipation, 53.

England and Wales, trend of death rate in, 283-284;
mortality statistics of, 287;
expectation of life in, 290.

Enjoyment of food, desirability of, 46-47, 201-202.

Enthusiasm in exercise, 95-96.

Equanimity, secret of, 115.

Ether, habit of using, as a stimulant, 242.

Eugenics, importance of, 157;
distinction between other branches of hygiene and, 157;
aim of, 163-165;
implies right care of racial germ-plasm, 165;
and wisdom of choice in marriage, 165-166;
ability of science of, to guide race to higher levels, 166-167;
knowledge of, both a personal advantage and a social necessity, 167;
main features of thoroughgoing program of, 167;
importance for future generations, 167;
grandest service of science to the human race, 167-168;
a remedy for degenerative ten